APPLICATION OF FLY ASH IN CONCRETE PRODUCTION: AN INTEGRATED STUDY OF ENVIRONMENTAL BENEFITS AND MATERIAL PROPERTIES
DOI:
https://doi.org/10.32782/apcmj.2024.3.12Keywords:
fly ash coal combustion products, composites, concrete, pavement repair, concrete pavement, aerodrome pavement, roadsAbstract
This study focuses on the feasibility of using fly ash to partially replace Portland cement in the concrete industry and its impact on concrete properties. The study concentrates on the sustainability of concrete production through ecological improvements, reduced consumption of natural raw materials, lower energy consumption, and reduced CO2 and dust emissions. The study begins with an overview of the future of concrete as a primary building material. It suggests using fly ash as a partial replacement for Portland cement. Fly ash is seen as a costeffective and readily available alternative material, especially in thermoelectric projects. To explore this, this study conducted a series of experiments to determine the optimum concrete proportion and the optimum percentage of fly ash to be used. The study employed a three-factor experimental plan to optimize the concrete formulation through mathematical and statistical methods. The focus was on the effects of fly ash content, water consumption, and aggregate proportion on the structure and properties of concrete. The experimental results show that introducing fly ash improves the mobility of concrete mixtures and does not reduce the strength of concrete by replacing cement within certain limits. In addition, the study investigated the effect of additives on concrete properties. Plasticizer LST-E and air-entraining agent SNV were used to evaluate their impact on concrete's compressive strength, water resistance, and frost resistance. The results showed that using these additives can reduce the amount of cement used while maintaining the required mobility of the concrete mixture. The study also looked at heat release during concrete hardening. It was shown that using fly ash to replace some of the cement could reduce the heat released from the concrete. In addition, increasing the curing temperature of concrete can decrease the amount of calcium hydroxide generated during hydration, thus improving the corrosion resistance of concrete and steel reinforcement in aggressive environments. In conclusion, this study demonstrates the feasibility of using fly ash as a partial replacement for Portland cement in concrete production, which not only improves the workability and durability of concrete but also helps to reduce costs and environmental impact. The study suggests that the use of fly ash in road and airport construction is promising, especially in precast prestressed slabs and monolithic cement concrete pavements.
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